This BPNN approach with two alarms was well suited, and it was not necessary to consider the problems of characterising the wave phases and pre-processing, as stated previously. Furthermore, BPNN is a mature technology, which is expected to develop rapidly in the future, and does not require complex hardware. Determining an initial location and magnitude of the event was not necessary for this technique. An existing seismic monitoring network can be used.

Particle swarm optimization is developed to estimate the model parameters of a 2.5-D sedimentary basin. PSO have been implemented on synthetic data and two field data. An observation has been made that PSO is affected by some levels of noise, but estimated depths are close to the true depths. The PSO results are well correlated with borehole samples and provide more geological viability than Marquardt results. Despite its long computation time, it is very simple to implement.

The current article focuses on plant diversity assessment in arid environments. Species richness and species evenness equations were used to meet the objectives. Remote sensing techniques were used to detect normalized difference vegetation index (NDVI) temporal changes. Two datasets were used to realize the NDVI, and post-chance detection (PCC) techniques were used to evaluate plant diversity status over a period of 4 years. The results show a recognizable loss in plant biodiversity.

Climate change studies are growing and related experiments are getting bigger and more complex. They are often conducted in remote areas where communications are limited. In cases like that the data can be transferred via a satellite connection, but these types of connections are slow. We found that by using the little known possibilities of LoggerNet software (the most popular data logger software in environmental science) it is possible to transfer quite a large amount of data.

Integrated geophysical techniques (ERT, SSR, and GPR) along the conducted profiles at the Great Pyramids of Giza have been successfully used to investigate the groundwater table and support hazard mitigation. The groundwater table elevation is 15 m under the Great Sphinx, which is safe, and at the Nazlet El-Samman it is 16–17 m.

In 2013 the scientists from the geophysical centre in Dourbes started a project to install a fully automated observatory in Antarctica. The ultimate aim is to have real-time data coming in to Dourbes every second. After evaluation of different data transfer protocols, we chose to use Message Queuing Telemetry Transport (MQTT) and receive the 1 s data with a negligible latency cost and no loss of data.

The focus of the paper is estimating profiles of water vapor and temperature with high accuracy from microwave radiometer measurements, performed for the month of August 2011 as part of the Integrated Ground Campaign during the Cloud Aerosol Interaction and Precipitation Enhancement Experiment (CAIPEEX-IGOC). To improve the accuracy of retrieved profiles Bayesian optimal estimation has been used along with optimized background data set.

This paper provides a technical review process in the area of airborne
acquisition of geophysical data, with emphasis for magnetometry. In summary,
it addresses the calibration processes of geophysical equipment as well as the
aircraft to minimize possible errors in measurements. The corrections used
in data processing and filtering are demonstrated with the same results as well as the evolution of these techniques in Brazil and worldwide.

High-power transmitters have been playing a significant role in deep electromagnetic exploration. However, a high-power transmitter needs high-voltage support, which is a potential risk for researchers. According to the actual situation of field exploration, we designed a wireless monitoring system. The system offers two advantages, the first of which is high security; the second advantage is simple operation.

Presented work allows estimation of buried source without any prior knowledge of underlying formation. This paper deals the application of continuous wavelet transform (CWT) and Euler deconvolution methods to estimate the source depth using magnetic anomalies. These methods are utilized mainly to focus on the fundamental issue for mapping the major coal seam and locating magnetic lineaments over Jharia coalfield, India.

The paper is aimed at the evidence of old quarries and other open mining sites in former Czechoslovakia. It is the result of several years of research. In the manuscript is described a very interesting history of the mapping in our country and especially the digital database and the web map building process. We register 10 000 historical mining sites that were active in the first half of the 20th century. The web map is designated for geologist, historians, landscape ecologists, biologists, etc.

We present a proof-of-concept space-flight instrument that can simultaneously make measurements of both the low- and high-frequency local magnetic field. Previously, this would have required two separate instruments that would normally have had to be mounted separately on long deployable booms to keep them from interfering. This new hybrid instrument is expected to be particularly useful on extremely small spacecraft, such as CubeSats, which can only accommodate a few instruments.

Ground-penetrating radar (GPR) is a powerful tool that uses electromagnetic waves to obtain 3-dimensional images of natural or man-made structures and subsoil. It is employed in a large variety of applications in which non-destructive investigations are required. This paper deals with the use of GPR for the evaluation of moisture content in wood. The results of our work are of great interest for the preservation of timber structures, as moisture content is highly relevant to wood deterioration.

A comprehensive, distributed network of in situ measurement stations gathering information on soil moisture has been set up in recent years at the Finnish Meteorological Institute's (FMI) Sodankylä Arctic research station. The network is used as a tool to evaluate the validity of satellite retrievals of soil properties. We present the soil moisture observation network and the results of comparisons of top layer soil moisture between 2012 and 2014 against ESA CCI product soil moisture retrievals.

The manual snow survey program of Finnish Meteorological Institute consists of numerous observations of natural seasonal snowpack in Sodankylä, in northern Finland. Systematic snow measurements began in 1911 with snow depth and snow water equivalent. In 2006 the manual snow survey program expanded to cover snow macro- and microstructure from snow pits. Extensive time series of manual snow measurements are important for the monitoring of temporal and spatial changes in seasonal snowpack.

The Sodankylä Geophysical Observatory has been producing ionospheric tomography data since 2003. Based on these data, one solar cycle of ionospheric vertical total electron content (VTEC) estimates is constructed. The measurements are compared against the IRI-2012 model, F10.7 solar flux index and sunspot number data. Qualitatively the tomographic VTEC estimate corresponds to reference data very well, but the IRI-2012 model are on average 40 % higher of that of the tomographic results.

Long-term records from high-precision GPS receivers are essential for studying geophysical movement. Existing, commercially available, precision GPS receivers are not intended for long-term, autonomous deployment. We have designed a GPS receiver that is better suited for this application. In this paper, we discuss the receiver design and compare its performance with that of some of the commercially available receivers.

This paper discussed the effect of temperature on the accuracy of submersible strain gauge pressure transducers. The results show that rapid change of temperature introduces errors in the water level reading while the absolute temperature is also related to the sensor errors. The former is attributed to venting and the latter is attributed to temperature compensation effects in the strain gauges. Performance tests are necessary before field deployment to ensure the data quality.

The existing current recorder is inadequate for continuous recording, precision, bandwidth, dynamic range, and input range. A new full waveform current recorder that is ideal for measuring current signal for electrical prospecting applications is presented. The full waveform current recorder is capable of measuring current with bandwidth from DC to 10 kHz, with a power spectrum density noise floor of 10 A/rt(Hz) at 10 Hz.

The article deals with the designation of fault detection on the island of Crete. The delineation is based on the integration method of remote sensing and GIS. The crucial finding is how to differentiate between faults and water streams. The results showed a robust approach to fault detection.

Historical surveys performed through the use of aerial photography gave us the first maps of the Arctic. Nearly a century later, a renewed interest in studying the Arctic is rising from the need to understand and quantify climate change. It is therefore time to dig up the archives and extract the maximum of information from the images using the most modern methods. In this study, we show that the aerial survey of Svalbard in 1936–38 provides us with valuable data on the archipelago's glaciers.

The main purpose of this paper is to introduce a receiver system for the synchronous acquisition of multiple electromagnetic signals in transient electromagnetic prospecting to achieve multiparameter and multichannel synchronous reception. The reliability, practicability, and data validity of the receiver were verified by different kinds of testing. It can be used for the reception of pseudorandom signals and distributed 3-D data, which can improve geophysical exploration efficiency.

Successful clustering of a dataset which is consistent with geological facts and laboratory and field studies is one of the results of this study. Since only REEs were used in this division, a good agreement of the results with lithology is considerable. Results show that unsupervised pattern recognition helps find some hidden information which would be difficult to obtain in usual ways. In addition, methods presented in this study will enable better interpretation of data.

This work describes a new approach to use fast X-ray fluorescence mapping as a tool for automated mineralogy applied on thin sections of plutonic rocks. Using a supervised classification of the spectral information, mineral maps are obtained for modal mineralogy and image analysis. The results are compared to a conventional method for automated mineralogy, which is scanning electron microscopy with mineral liberation analyzer, showing a good overall accuracy of 76 %.

We report on the history and recent developments of the Tatuoca magnetic observatory in Brazil. This observatory is located close to the geomagnetic equator and within a region of strong main field dynamics. Starting from 2015, we have installed new instrumentation and a new datalogger system. In the paper, we also comment on the challenges of doing absolute measurements at the geomagnetic equator.

A numerical inversion approach to detect and localize inclusions in thick walls under quasi-periodic natural solicitations is presented. It is based on a preliminary analysis of surface temperature field evolution with time. This analysis is improved by taking advantage of a priori information provided by ground-penetrating radar reconstructions. In this way, it is possible to improve the accuracy of the images achievable with the stand-alone thermal reconstruction method.

Intrinsic permeability of snow is an important parameter that regulates snow–atmosphere exchange. Current permeability measurements require specialized equipment for acquisition in the field and have increased variability with increasing snow heterogeneity. To facilitate a field-based, volume-averaged measure of permeability, we designed and assembled an acoustic permeameter. When using reticulated foam samples of known permeability, the mean relative error from known values was less than 20 %.

The hardware and software used to collect eddy-covariance ecosystem
fluxes of carbon dioxide, heat, and water vapor at a high-elevation
subalpine forest site over 17 years are described. Over time,
software/hardware improvements have increased the system robustness,
leading to a successful 10 Hz data-collection rate of better than 99.98 %. We also provide philosophical concepts that shaped our data system design and are applicable to many different types of environmental data collection.

Institute of Geophysics and Problems of the Earth Ltd. (Kiev, Ukraine) has developed, patented and been applying in practice for more than 10 years the innovative NMR technology of direct detection of hydrocarbon reservoirs at a depth of up to 5 km without interpretation. Absolute data of deep magтenic resonance sounding are especially in demand during sharp plummeting of oil prices since it significantly reduces exploration risks while saving the exploration budgets of companies.

Carbon dioxide is the most abundant greenhouse gas emitted due to human activities. Changes in atmospheric columns of carbon dioxide can be measured accurately using ground-based Fourier transform spectrometers, which are operating in the near-infrared spectral region. Our measurements at Sodankylä reveal a significant increase of column carbon dioxide since the start of the column measurements at Sodankylä in early 2009.

Lamp measurements used for the UV irradiance calibration of two Brewer spectrophotometers operated for 20 years in Jokioinen and Sodankylä, Finland, were examined. Temporal development of the responsivity after fixing the irradiance measurements into a specific scale was studied. Both long-term gradual decrease and abrupt changes in responsiveness were detected. Frequent-enough measurements of working standard lamps were found necessary to detect the short-term variations in responsiveness.

The paper described an extensive in situ data set of bulk snow depth, snow water equivalent, and snow density collected as a support of SnowSAR-2 airborne campaign in northern Finland. The spatial and temporal variability of these snow properties was analyzed in different land cover types. The success of the chosen measurement protocol to provide an accurate reference for the simultaneous SAR data products was analyzed in the context of spatial scale, sample size, and uncertainty.

Sodankylä, in the heart of the Arctic Research Centre of the Finnish Meteorological Institute in northern Finland with temperatures ranging from −50 to &plus;30 °C, provides a challenging location for numerical weather forecasting (NWP) models. In this article, the use of measurements performed in Sodankylä for near-real time online verification of NWP models is described. A more specific case study of three different radiation schemes, applicable in NWP model HARMONIE-AROME, is also presented.

The paper presents the initial findings of the Arctic Snow Microstructure Experiment in Sodankylä, Finland. The experiment observed the microwave emission of extracted snow slabs on absorbing and reflecting bases. Snow parameters were recorded to simulate the emission upon those bases using two different emission models. The smallest simulation errors were associated with the absorbing base at vertical polarization. The observations will be used for the development of snow emission modelling.

Multiobjective optimization is used to design Pareto optimal greenhouse gas (GHG) observing networks. A prototype GHG network is designed to optimize scientific performance and measurement costs. The Pareto frontier is convex, showing the trade-offs between performance and cost and the diminishing returns in trading one for the other. Other objectives and constraints that are important in the design of practical GHG monitoring networks can be incorporated into our method.

A two-step procedure to calibrate the spectral sensitivity of auroral all-sky (fish-eye) cameras is outlined. First, center pixel response is obtained by the use of a Lambertian surface and a standard tungsten lamp. Second, all-sky flat-field correction is carried out with an integrating sphere.